In the related art, as light-emitting devices including light emitting elements which are formed on a substrate, a light-emitting device using a ceramic substrate, a light-emitting device including an organic resist layer as an insulating layer on a metal substrate and the like have been known.
As an example of the ceramic substrate, PTL 1 discloses a ceramic substrate in which a wiring is formed on the substrate by sintering silver-based conductor paste.